The radio layer moves the bits from master to slave, or vice versa. It is a low-power system with a range of 10 meters operating in the same 2.4 GHz ISM band as 802.11. The band is divided into 79 channels of 1 MHz each. To coexist with other networks using the ISM band, frequency hopping spread spectrum is used. There can be up to 1600 hops/sec over slots with a dwell time of 625 Hsec. All the nodes in a piconet hop frequencies simultaneously, following the slot tim- ing and pseudorandom hop sequence dictated by the master. versions of Bluetooth